package com.syt.mall.product.web;

import com.syt.mall.product.entity.CategoryEntity;
import com.syt.mall.product.service.CategoryService;
import com.syt.mall.product.vo.Catelog2Vo;
import org.redisson.api.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;

import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

@Controller
public class IndexController {

    @Autowired
    private CategoryService categoryService;
    @Autowired
    private RedissonClient redisson;

    @Autowired
    private StringRedisTemplate redisTemplate;


    @GetMapping({"/","index.html"})
    public String indexPage(Model model){
        // TODO 1.查出所有的一级分类
        List<CategoryEntity> categoryEntities = categoryService.getLevel1Categorys();
        model.addAttribute("categorys",categoryEntities);
        return "index";
    }

    @ResponseBody
    @GetMapping("/index/catalog.json")
    public  Map<String, List<Catelog2Vo>> getCatalogJson(){
        Map<String, List<Catelog2Vo>> map =categoryService.getCatalogJson();
        return map;
    }



    /*****************************************************************以下代码为测试代码**********************************/
    @ResponseBody
    @GetMapping("/hello")
    public String hello(){
        //1.获取一把锁,只要锁名一样,就是同一把锁  默认加的锁都是30s时间
        RLock lock = redisson.getLock("my-lock");
        //1).锁的自动续期,如果业务超长,运行期间会自动给锁续上新的30s,不用担心业务时间长,锁自动过期被删除
        //2).加锁的业务只要运行完成,就不会给当前锁续期,及时不手动解锁,锁默认在30s以后自动删除
        //2.加锁
       // lock.lock(); //阻塞式等待

        lock.lock(10, TimeUnit.SECONDS); //指定时间 10s自动解锁 ,自动解锁时间一定要大于业务的执行时间
        //问题: lock.lock(10, TimeUnit.SECONDS) 在锁时间到了以后,不会自动续期
        //1.如果我们传递了锁的超时时间,就发送给redis执行脚本,进行占锁,默认时间就是我们指定的时间
        //2.如果我们未指定锁的超时时间,就使用30*1000[LockWatchdogTimeout看门狗的默认时间] ,每隔10秒都会自动再次续期,续成30秒
        // 只要占锁成功,就会启动一个定时任务[重新给锁设置过期时间,新的过期时间就是看门狗的默认时间]
        //  internalLockLeaseTime[看门狗时间]/3 ,10s

        //最佳实战
        //lock.lock(10, TimeUnit.SECONDS); 省掉了整个续期操作.手动解锁
        try{
            System.out.println("加锁成功,执行业务...."+Thread.currentThread().getId());
            Thread.sleep(30*1000);
        }catch (Exception e){

        }finally {
            //3.解锁  假设解锁代码没有运行,redisson会不会出现死锁
            System.out.println("释放锁"+Thread.currentThread().getId());
            lock.unlock();
        }

        return "hello";
    }



    //保证一定能督导最新数据,修改期间写锁是一个排他锁(互斥锁),读锁是一个共享锁
    //写锁没释放,读就必须等待
    //写+读: 等待写锁释放
    //写+写: 阻塞方式
    //读+写:有读锁,写也需要等待
    //读+读: 相当于无锁,并发读只会在redis中记录好,所有当前的读锁,他们都会同时加锁成功
    //只要有写的存在,都必须等待
    @GetMapping("/write")
    @ResponseBody
    public String writeValue(){
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        String uuid = null;
        RLock rLock = lock.writeLock();
        try {
            //1.改数据加写锁,读数据加读锁

            rLock.lock();
            uuid = UUID.randomUUID().toString();
            Thread.sleep(30*1000);
            redisTemplate.opsForValue().set("writeValue",uuid);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }finally {
            rLock.unlock();
        }
        return uuid;
    }

    @GetMapping("/read")
    @ResponseBody
    public String readValue(){
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        String uuid = null;
        //加读锁
        RLock rLock = lock.readLock();
        rLock.lock();
        try {

            uuid = redisTemplate.opsForValue().get("writeValue");
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            rLock.unlock();
        }
        return uuid;
    }

    /**
     * 分布式闭锁
     */
    @GetMapping("/lockDoor")
    @ResponseBody
    public String lockDoor() throws InterruptedException {
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.trySetCount(5);
        door.await(); //等待闭锁都完成
        System.out.println("放假啦!!!");
        return "放假了...";
    }
    @GetMapping("/gogogo/{id}")
    @ResponseBody
    public String gogogo(@PathVariable Long id){
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.countDown();//计数减一

//        CountDownLatch
        return id+"班人都走了....";
    }

    /**
     * 车库停车
     * 信号量也可以用作分布式限流 限流
     */
    @GetMapping("/park")
    @ResponseBody
    public String park() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        park.acquire();//获取一个信号,获取一个值,占一个车位
        boolean b = park.tryAcquire();
        if (b){
            //执行业务
        }else {
            return "error";
        }
        return "ok";
    }

    @GetMapping("/go")
    @ResponseBody
    public String go() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        park.release();//释放一个车位

        return "ok";
    }
}
